New Spirals Boost Recovery at Northam Chrome

Mineral processing equipment supplier Multotec reported that one of its gravity-separation customers, Northam Chrome Producers, is realizing improved recoveries, better grades and higher yields following the installation of Multotec spirals at its recovery plant.

The decision to replace the existing spirals was taken by the chrome producer following extensive testwork performed by both Northam and Multotec. Results from the testwork, said Multotec, indicated that its spirals outperformed the competitor units installed in the plant. Testwork was later revalidated at Multotec’s in-house technology division in Spartan, Gauteng, South Africa, according to the company.

Based on the outcome of these trials, Northam Chrome Producers decided to replace the existing spirals—which had reached their end of life—with Multotec spiral technology. “Tests showed that by using the Multotec spirals, the plant would be able to increase recoveries by an additional yield of 6%,” said Multotec’s Graeme Smith, who noted that his company removed 172 spiral assemblies from the existing recovery plant and replaced them with 72 Multotec spiral assemblies. These comprised Multotec HX5 and Multotec HX3 spirals with feed tonnage capacities ranging from 4–9 metric tons per hour (mt/h) per start.

Following installation of new Multottec HX3 and HX5 spirals similar to that shown here, Northam’s plant yield increased from 21% to almost 30%.

Smith said one of the biggest challenges of the two-month project was retrofitting the new spirals into the existing structure. This required extensive work by Multotec’s in-house drawing office, which undertook all the drawings and confirmed the new layout of the plant, while also presenting the modifications needed to the structure to accommodate the new installation.

The project was overseen by Smith and field service technician, Raymond Masinga. “The commissioning of the plant was an easy exercise. It started up the same day and immediately started outperforming the earlier test results,” Smith said. He reported that the entire plant’s yield is now closer to 30%, compared to the average of 21% in 2014.

Multotec engineers determined that the cost of the spiral assembly is about 0.004c/feed ton, with Northam Chrome Producers expected to see a return on its investment within a four-year period.

Clariant Collects New
Chemical Production Assets

Clariant, a major specialty chemicals supplier, recently announced investments aimed at increasing the footprint of its Mining Solutions business and improving its product portfolio, customer base and technical expertise.

Clariant acquired Chemical & Mining Services, a provider of specialty chemicals and technical services to mining industry clients located primarily in Australia. Clariant has also acquired the specialty mining chemicals business from SNF Flomin, a U.S.-based subsidiary of the SNF Group, which manufactures and distributes reagents for the minerals processing industry. No additional details regarding either acquisition were disclosed.

Clariant also said it has opened a new facility and expanded one of its current facilities in North America. The company inaugurated its Mining Application and Development Center in Tucson, Arizona, calling it “the regional hub for mining research.” Its close proximity to key mining customers will allow for more and better cooperation on customized products and solutions, according to the company. In addition, its plant in Reserve, Louisiana, has been expanded and is now able to blend chemicals for the mining industry.

“These investments strengthen our global position as a leading supplier of specialty chemicals to the mining market,” said John Gordon, global head of Clariant Mining Solutions. “Chemical & Mining Services current business and products are a complementary strategic fit to our own and also provide us with specialized technical expertise. SNF Flomin, while U.S.-based, supplied to customers worldwide and thus allows us to expand geographically and serve our customers with an increased product and service portfolio.

“Finally, the investments in North America enable us to become a stronger player in this region’s mining market and better support our customers by stepping up both our research and supply chain capabilities.”

App Monitors Filter Cloth Performance

Valmet launched a new app at the FILTECH exhibition in Cologne, Germany, during October that can be used for monitoring the performance of filter cloth in filter presses by gathering information with RFID technology. “We were able to use the information on cloth lifetimes, the reasons for cloth removal and cloth consumption to optimize the whole filtration process. In addition, this information helps process operators to better monitor the filter itself,” said Sanna Uusitalo, product manager–filtration at Valmet.

RFID tags submit information to be used in the follow-up and analysis of the whole filtration process, saving money with planned maintenance and reduced filter downtime. “The application also enables remote support from our filtration experts. By enabling us to see inside the process, the application helps us and our customers to optimize the whole filtration process,” Uusitalo said. RFID technology has been in use for decades, however, Valmet said it is the first to use it for filter cloth.

Veolia to Supply Effluent
Treatment Facility for Brucejack

Pretium Resources selected Veolia Water Technologies Canada to supply the new effluent treatment facility for the Brucejack gold mine in British Columbia, Canada. Brucejack is one of the largest and highest-grading undeveloped gold projects in the world.

Veolia will supply proven proprietary processes to treat up to 10,000 m3 per day of effluent water from the mine. The permanent effluent treatment system will consist of several technologies, which were selected for their robustness and compactness, starting with the Actiflo clarification process for primary metals removal. The water will be further polished by a Hydrotech Discfilter, which gives added insurance in meeting very stringent discharge criteria. Startup of the new effluent treatment facility is scheduled for spring 2017.

Veolia said this contract follows months of extensive collaboration and testing to ensure that the most stringent environmental discharge limits will be met. The test work that was carried out at Veolia laboratories in Montreal has been largely used in support of the extensive permitting work that has been prepared by Pretium for the Canadian and Provincial authorities. “Based on Pretium’s investment in several months of test work, it was clear how committed they are to ensuring their environmental stewardship,” said David Oliphant, vice president, business development heavy industry for Veolia Water Technologies Canada.

Veolia started working with Pretium in spring 2014 when the company needed to dewater Brucejack’s underground workings during its exploration phase. Veolia supplied a mobile Actiflo water treatment plant, which it has operated since. This temporary facility provided Pretium with extremely valuable seasonal operational data for future reference. As the Actiflo clarification process will also be installed in the new effluent treatment facility, it gives Pretium the confidence that the system meets the stringent requirements of low level metals and total suspended solids while dealing with variable feedwater.